/Engine/Plugins/Runtime/SoundFields/Source/SoundFields/Public/SoundFields.h
Transcoder streams are fed a soundfield audio packet with either a different format entirely, or the same format and different settings. Specifying and returns a Transcoder Stream is not necessary if CanTranscodeSoundfieldFormat and ShouldReencodeBetween always returns false.
virtual [TUniquePtr](API\Runtime\Core\Templates\TUniquePtr)< [ISoundfieldTranscodeStream](API\Runtime\AudioExtensions\ISoundfieldTranscodeStream) > CreateTranscoderStream ( const [FName](API\Runtime\Core\UObject\FName) SourceFormat, const [ISoundfieldEncodingSettingsProxy](API\Runtime\AudioExtensions\ISoundfieldEncodingSettingsProxy) & InitialSourceSettings, const [FName](API\Runtime\Core\UObject\FName) DestinationFormat, const [ISoundfieldEncodingSettingsProxy](API\Runtime\AudioExtensions\ISoundfieldEncodingSettingsProxy) & InitialDestinationSettings, const [FAudioPluginInitializationParams](API\Runtime\AudioExtensions\FAudioPluginInitializationParams) & InitInfo )